Review on Cyful Adjustable Tapping Professional with Customizable Capacity by Russ Mashlan

I believe the term 1/2" refers to the thread size of the tap. I bought two new 9/16-18 taps and they did NOT fit this handle! 5/16". And they didn't fit. I'm sick of waiting for the slow delivery of non-essential Revains products so I'm not sending the pen back. Instead I took a dremel and opened up the embossed area on the faucet handle and ended up sanding down the clamp area. Also. Might not work with a heavy steel hammer without breaking, but for threading a synthetic rifle stock to accept a QD mug it worked well after my mechanical modification of this mild steel hammer grip.